Adducts of 5,7,9(11)-pregnatrien-3,20-dione



. dione. come apparent hereinafter.

Patented Nov. 11, 1952 UNITED STATES PATENT OFFICE ADDUCTS F 5,7,9 (11) -PREGNATRIEN-A sen-mom:

Robert H. Levin, A Vern McIntosh, Jr., and George B. Spero, Kalamazoo, Mich., assignors to The Upjohn Company, Kalamazoo, Mich., a

corporation of'Miehigan No Drawing. Application September 1, 1950,

Serial No. 182,881v

9 Claims. (01. zoo-239.55)

The present invention relates to adducts of 5, '7, 9(11)-pregnatrien 3,20-dione with certain dienophilic acids, anhydrides, and esters, and to a process for the production thereof.

' The compounds of the present invention may berepresented by the structural formula:

wherein A is an adduct radical derived from a dienophile selected from the group consisting of maleic acid, maleic anhydride, and maleic acid diesters containing. from oneto eight carbon atoms, inclusive, in the esterifying' group.

It is an object of the present invention to provide a novel group of compounds which are useful in the preparation of steroid compounds containing an oxygen atom at carbon atom eleven. Another object of the invention is the provision of a process for the production of the novel come pounds, adducts of 5, '7, 9(11) -pregnatrien-3, 20- Other objects of the invention will be- The:compounds of the present invention, as previously stated, are .useful in the preparation of steroid compounds having an oxygen'atom attached to carbon atom eleven. Such compounds are of particular interest in the field of steroid research due to the biological activity of the corticalhormones and certain known derivatives thereof, whichoxygenated steroids are known to,

have biological eifects differing markedly from the unoxygenatedisteroids. :It is,.therefore, of importance to investigate the oxygenated derivatives of such adducts, particularly those oxygenated at carbon atom eleven, as well as to investigate the biological activity of the adducts themselvesand their transformation products. The importance of such investigation is moreover emphasized by the acute shortage of adrenal cortical hormones, and the absence of any present suggestion for alleviation of the'said shortage except through organic synthesis. V

Novel compounds of the present invention which are of particular interest are those com,-

pounds of the above generic formula wherein the adduct bridge (-A) is represented by the graphic formula:

e-ooon 11 which is representative of the maleic anhydride adduct.

The compounds of the invention are usually colorless crystalline solids. The acid anhydride adduct is readily converted to the free acid adduct by hydrolysis. The acid or anhydride adduct is readily converted into diester adducts by esterification with conventional reagents suchas the diazoalkanes [Wilds et al., J. Org. Chem. 13, 763 (1948) Conversely, the diesters may be hydrolyzed to the dibasic acid which in turn may be converted into the anhydride either by'heat alone or preferably with a mild dehydrating agent such as acetic anhydride and the like.

The 5. 7, 9(11) -pregnatrien-3,20-dione adducts of the present invention are prepared by the con- 3 trolled oxidation of a 3-hydroxy-5,7,9(11) -pregnatrien-20-one adduct of the formula:

wherein A has the value previously assigned. These 3-hydroxy adducts are in turn prepared from 3-acyloxy-5,7,9(ll) -pregnatrien-20-one adducts, of the formula:

CHI

wherein Ac is the residue of an organic carboxylic acid containing from one to ten carbon atoms inclusive, and A has the value previously assigned. In such compound. AeO represen s an ester of th -hjzdrexy oup wi h a carb xylic acid containing up to and including ten carbon atoms. Among the acids which can be used are formic, acetic, propionic, butyric, valeric, hexanoie. heptanoie, octanoic, decanoic, succinic, elute cyelopentanoic, eyclohexanoic, benz ic. teluic. and the lik 7 Preferred a ds ar th s containing rom one to ght a n atoms, inelusive, and especially such lower-aliphatic acids. The acids may also contain substituents, such as halo, alkyl, and methoxy, which are non-reactive under the reaction conditions employed. The 3-hydroxy compounds are prepared from the 3- acyloxy compounds saponification, which procedure is productive of the 3-hydroxy ketone diacid, which can then be converted to the anhydride or diester if desired, as more fully described hereinafter.

The adducts of 3-.acyloxy-5,7,9(l1) -pregnatrien-ZO-ones are conveniently prepared by the selective oxidation of an enol ester of an adduct of 3-acyl0xybisnor-5,7,9 (11) cholatrien-22-al, represented by the formula:

(IJH: H-Aevloxy CH3 iently prepared by subjecting an adduct-of a 3- 4 acyloxybisnor-5,7,9(11) -cholatrlen-22-al, of the formula:

wherein A and Ac have the values previously given, to the action of an acid anhydride or an acid halide in the presence of an alkaline salt of the acid. The starting adducts of 3-aeyloxybisnor-5,7,9 ('11) -cholatrien-22als can be prepared from adducts of 3-esters of dehydroergosterol by selective oxidation as described and claimed in the copending application Serial 111,- of Robert Levin, filed August 18, 19.49, and as more fully descr bed her after,

The 3-esters ofdehydroergosterol, from which the 3 acyloxybisnor 5,7,9,(11) chloatrien- 22-al adducts are prepared, can be synthesized in several ways starting with ergosterol. For example, ergosterol can be transformed to dehydroergosterol with mercuric acetate according to known methods [Windaus et 'al., Ann. 465, 157 (1928)] and the 3.-hydroxy group of the dehydroergosterol acylated by known procedure. Al ternatively the 3-hydroxy group of ergosterol can be acylated prior to the preparation of the dehydro derivative, a procedure which is particularly preferred in the preparation of the 3- acetoxy derivative. The adducts of dehydroergosterol are then prepared by the addition of maleic anhydride or the like to dehydroergosterol .or a 3.-ester thereof according to known methods [Honigmann, Ann. 508, 89 (1934)]. The anhydrides can then be converted to'their corresponding acids and esters if desired.

The ester group, when present in the 3-position of dehydroergosterol, is for the purpose of protecting the 3ehydroxy group in subsequent chemical reactions. For this purpose any convenient ester of an organic carboxylic acid, which is nonreactive under the conditions of the reaction, is suitable. The preferred acids are the fatty acids such as formic, acetic, propionic, butyric, valerlc. hexanoic, heptanoic, 'octanoic, decanoic; .dibasic acids such as malonic, succinic, phthalie; cycloaliphatic acids such as eyclopentanoic and .cyclohcxanoic; and aromatic acids such as benzoic, tol-uic, and thelike. The acids may also contain substituents such as halogen, alkyl, the methoxy radical, and the like, and these substitutents will be carried throughout the synthesis. If desired. the acyl group can be changed to another acyl group by sap'onifying the ester to give a 3-hydrox-y compound, which can then be re-esterified as previously described.

A preferred method for preparing some of the dehydroergosteryl adducts comprises the saponification of a 'B-acyloxy-adduct of dehydroerg'osterol with dilute alkali followed by acidification. The 3-hydroxy dicarboxylic acid thus formed can be converted to the 3-hydroxyanhydrid'eby heat, or it can be converted to any desired 3-acylox-y anhydride adduct by heating under reflux with the appropriate acid anhydride or chloride in pyridine solution. Dialkyl esters of the previously mentioned dicarboxylic acid adducts can 'be'prepared bysub'jectlng the acid to the action of an esterification reagent such as diazoalkane [Wilds et al., J. Org. Chem. 13, 763 (1948)], e. g., diazomethane, diazoethane. diazobutane, and the like.

The selective oxidation of an adduct of dehydroergosterol, or a 3-ester thereof, to produce an adduct of 3-hydroxybisnor-5,7,9(11)-cholatrien-22-al, or a B-ester thereof, is accomplished by dissolving the dehydroergosteryl adduct in a suitable solvent, cooling'to about minus 80 to plus 30 degrees centigrade, and passing ozone into the solution until about 1.0 to 1.25 moles of ozone per mole of adduct have been absorbed. The temperature of the solution should be maintained below plus 30 degrees centigrade, preferably between a temperature of minu 30 and minus 70 degrees centigrade, during the addition of ozone, although temperatures as low as minus 80 and as high as plus 30 degrees centigrade are operative. The lower temperatures of the preferred range are readily obtained by cooling' the solution of the adduct with a bath of solid carbon dioxide in acetone or the like, although various other methods of cooling can be used. Many of the customary solvents used in ozonizations such as chloroform, acetic acid, carbon tetrachloride, ethylene chloride, methylene chlo-' ride, and the like, can be used.

The ozonides are then decomposed under reducing conditions, that is, in the absence of oxidizing agents, whether added or formed in the Course of the reaction by products of decomposition of the ozonide. This means that excess oxygen formed by decomposition of the ozonidels prevented :from forming hydrogen peroxide by combining with any moisture present, and that molecular oxygen is prevented from oxidizing the aldehyde thus formed. This can be conveniently accomplished by decomposing the ozonide in glacial acetic acid by the addition of finely-powdered zinc.

As is conventional with ozonizations when conducted in solvents, other than glacial acetic acid, the solvent used for ozonization is replaced, after completion of the ozonization, by adding glacial acetic acid and removing the lower-boiling solvent byvfractional distillation. Alternatively, the solvent can be removed by careful warming under reduced pressure prior to the addition of glacial acetic'acid,if desired.

. After decomposition of the ozonide and removal of the zinc, the aldehyde can be recovered by diluting the acetic acid with water, or in other conventional manner, such as by formation of an aldehyde derivative, e. g., the dinitrophenylhydrazone.

Adducts of 3,ZZ-diacyloxybisnor-5,7,9(11),20 (22)'-cholatetraenes [22-enol-esters of adducts of 3-acyloxybisnor-5,7;9(l1)-cholatrien-22-alsl can be conveniently prepared by heating the corresponding 3-hydroxy or acyloxy aldehyde maleic acid, maleic acid anhydride, or maleic acid ester adduct with a large excess of an organic carboxylic acid anhydride in the presence of a small amount of the alkali metal salt of the acid corresponding to the anhydride employed or an acid catalyst. such as para-toluene sulfonic or suliuric acid. The preferred anhydride is acetic anhydride, but other anhydrides, such as propionic, butyric, valeric, hexanoic, octanoic, and decanoic anhydrides, as well as benzoic acid anhydride, ortho-toluic acid anhydride, and the like, are also operative. The acid anhydrides can also be substituted by non-reactive groups, such as .halo,-alkyl, and methoxy, as in the case of for decomposition of such compounds.

6 chloroacetic, ortho-toluic, or inethoxybenzoic acid anhydrides. The reaction can be conveniently followed by observing the color changes in the reaction mixture, optimum yields being obtained by discontinuing the application of heat when the color of the solution changes from yellow to brown. Ordinarily the reaction is heated at about degrees centigrade for from about four to six hours, but temperatures as low as 100 andas high as degrees centigrade are also. operative. The reaction is usually conducted at the boiling point of the anhydride, but in the case of the higher-boiling anhydrides, such as benzoic anhydride, a suitable temperature control, suchas 100-150 degrees centigrade, must be used, since the adduct otherwise tends to decompose in the higher temperature range. If a 3- hydroxy aldehyde adduct is thus reacted with an anhydride, the hydroxy group will beacylated. and, simi1arly,if a maleic acid adduct is used instead of a diester or an anhydride, the anhydride will be formed. The enol ester can be isolated by removing the excess anhydride under reduced pressure, and separting the enol ester from alkali metal salts, which procedure yields a product suificiently pure for most purposes, but which can be further purified by recrystallization, from acetone-water, acetone-pentane, or like $01- vents. if desired.

The ozonization ofthe thus-prepared enol a-cylate to produce 3-acyloxy-5,7,9(11)-pregnatrien-20-one adducts involves dissolving the enol ester in a suitable solvent, cooling to about minus eighty degrees centigrade to plus thirty degrees centigrade, and passing ozone, ozonized air, or ozonized oxygen into the solution until about 1.0 to about 1.25 moles, preferably 1.0 to 1.1 moles, of ozone per mole of adduct have been absorbed. The addition of ozone to the 20:22 double bond is so rapid that only a small amount of ozone escapes from the reaction mixture, and the amount of ozone ordinarily required therefore closely approximates the theoretical amount. Loss to the solvent, if any loss occurs, must be taken into consideration in calculating the amount of ozone to be introduced. The temperature of the solution should be maintained below plus thirty degrees centigrade, preferably between a temperature of minus thirty and minus seventy degrees centigrade, during the addition of ozone, although temperatures as low as minus eighty and as high as plus thirtydegrees centigrade are operative. The lower temperatures-oi. the range are readily obtained-by cooling the solution of the adduct with a bath of solid carbon dioxide in acetone or the like, although various other. methods of cooling may be employed.

Many of the customary solvents used in ozonizations, such as chloroform, methylene chloride, ethylene chloride, carbon tetrachloride, acetic acid, and the like, can be used for the ozonization reaction. a

The 20:22 ozonides thus produced are then decomposed under conditions normally employed This can be accomplished conveniently by decomposing the ozonide with hydrogen peroxide, by hydrolysis, with zinc in glacial acetic acid, or by a catalytic amount of colloidal metal such as silver, platinum, or palladium in a solvent, such as glacial acetic acid, alcohol, or ethyl acetate, in which latter case reductive conditions, e. g., a hydrogen atmosphere, are also employed. The us f ductive conditions is well established in the art [Hill and Kelly, Organic Chemistry, page 53,

The-Blackiston Company, Philadelphia (1934).; Qhurchr et al., J. Am. Chem. Soc. 516, 176-91844 (1934);" Gilman, -Organic- Chemistry,'- second edition, page 636, John Wiley and Sons, 'New York1u943i; Long, Chem. Reviews 2'7, 452-454 {159.40% I As i's conventional with decomposition. of- 020- nides with zinc, when the ozonizations are con-: ducted in solvents other than glacia1 acetic acid. the solvent used for the ozonization is replaced, after: completion of the ozoniz'ation, by addingglacial acetic" acid and. removing the lowere-boilthe solvent by fractional distillation, or the: solvent can be removed by careful warmingv under reduced pressure prior to. the addition of acetic acid, if desired. After decomposition of the :22 'oz-onide 'andremoval of the metal, the ketone can be recovered .by diluting the acetic acid- -wtth water, or by other conventionalprocedure for the recovery of ketonsysuch as by formation oi a carbonyl derivative;e. 'g.,- the 2,4 dinitrophenyl hy'drazone. Recrystallization 'i-rom acetone or the like results in a more highly purified ketone product. The 3-hydroxy ketones are prepared by saponification of the s-acyloxy' group-to ive the 3-hydr'oxy rot-one diacid, which can then be converted to a die ter, iidesired, or

the: anhyd-ride. The anhydride is readilyprepared by heating the free diacid ina vacuum,

while the esters are readily prepared from the free. acid by treatment with diazomethane, diaz' oethane, and the like. 7

The 5,7,9 11 =pregnatrien-3,20-dione adducts of the present invention are prepared by the controlled oxidation of the correspondin a-h droxy compound to convert the 3-hydrox'y group therein to a ket-o group. This is conveniently accomplishedbymixing the selected maleic acid, m'aleic anhydri'de, or maleic acid diester adduct of 3-hydroxy-5,7-,9(.11 )-pregnatrien-20-one with from one to four molar equivalents of chromic acid, from one to a slight excess over one equivalent being preferred. The reaction is conducted in an acetic-acid medium, in the presence of a, catalytic amount of sulfuric acid. The temperature at which the reaction is conducted is between about and twenty-six degrees centignade, which is conveniently maintained by cooling the reactionin a water 'bath while adding a mixture of chromium trioxide, a small quantity oi-w-ater and .a catalyticquantityof sulfuric acid, all. in acetic acid, dropwise to a solution of the 3-hydroxy compound in acetic acid. The reaction is conveniently followed by observing the color change of the chromic acid. Upon completion oithe reaction, the product is recovered in conventional manner... such as by drowning out by the dropwise addition of water-to the reaction mixture; Ifdesired, the product may be recrystallized from ethyl acetate, acetone, or like solvents, togive a m-ore highly purified product.

An especially preferred procedure for: recovery of; the keto acid involves dissolving. the reaction pnoduot-in-abase, e. g.,-,sodium hydroxide, careiullyacidifying with dilute hydrochloric acid,

cooling the resulting mixture to cause precipitation or thecrys-talline product;

, The following examples are illustrative of the .process &I1d-I J-IOf l 1l0t5;0f the present invention,- but are not to be construed' as-l-imi-ting.

Preparation 1 -Di*m;ethyl 3 ntaieate addu'ct of ciehymioergo-stemi hematite; Ia solution-M21 grams of'dimcthyl maleate adduot; of dehydroergosterol. in169i-lmilliliters of warm pyridine was added9.-5 millilitersoi henzoyl chloride. After standing atroom temperature for fifteen minutes, the mixture was. poured int-0,1400 milliliters of ice-water and the solid removed by filtration, dried, and recrystallized from acetone. There. was thus obtained 26A grams "of dimethyl maleate. adduct of clehydroergosteryl benzoate, melting at 20.3 to;2105.5. degrees. centigrade'. Preparation 2.- Dimeth*yl maledte 'adduct 0 dehydroergosteryZ acetate In a ann r ea en ial y that descr be Prepara qn- .15m: dime hyl; male te dduct; of. dehydroerg st l a eta me tin at t .79 degrees nt smde. was p pa ed fr m-the dimethyl e t' dd c oi deh o rgostem nd e y chloride.

Preparation8.;1Zimethyl; melee-to qdd'uct; 0/ I dehgdroergosteryl formate A solution of six grams; of dimethyi maleate adduct of; dehydroergesterol in fifty'mil-liliters of 87 percent formic acid was heated unclerrefiux for one hour, cooled, and the dimethyl maleate adduct oi dehydroergosteryliormate filtered therefrom. Upon crystallization fromacetone. thepurif ed material meltedat 177.5 to .-1"78.5 degrees centigrade. a

1 Preparation 4'.' Male'ic acid adore-toidehydroereosterol A solution of 2.0.- grams. or sodium hydroxide in twenty millimetersof water was added. to a. solution of 1.73 .gr-ams of themaleic anhydricleadduct of r'iehydroergosteryl acetate- M P. 2309232 degrees' centigrade), in forty-millilitersof diox ane. The mixture solidified, but dissolved on addition of. 300; milliliters of .water and heating. to.ei-ghty degrees centigrade. ififter half an hour the solution-,was cooled andmade acid with aqueous. three normal hydrochloric acid, to give 1.61 grams of precipitate. Qn crystallization from a, dioxanewater mixtm'e, the. rnal eic acid; adduotofdehydroergosterol. melted at 190-192 degrees centigrade,

3-hptamer wry-deiigydroefgosterol "ffl-ie maleic acid, adduct. of, dehyuroergoisterol from Preparation 4 was dissolvedi'na mixture of seven milliliters. of warm pyridine and. idfiltte'en millilitersof heptylic anhydride',,and' the mixture he te nd r. 'flux for rifi h'our. Atoutpeiehti percent of the reaction. solvent was removed. und'arfredfuce'd. pre sure, and the residue then dis;-

solved in methyl alcohol. The methyl alcohol ated and cooled. to yield G'. iyd1f dB ari u t' 0f hea anoig i rx'yf .yd qer cste ol, melti 86;-

1 1-5 e'erees'ce ieradai Pre aration; 6:. i l 1 2 aohudr de adduc 013-.- c taanbi'snor an961A)-- lwla rianrzzeal j A solution or 5.35. gramssor-the maleic' anhydri'deiadduct or: 3%beta alcetoxydehydroergosterol I in 107 milliliters-of.methylene:chioridezwasncooled to about seventy degrees: centigrad'e" and occurred; until: 505 milligrams of? ozone had been -te;bsorbed. 'Iihe;v temperature of: the solutionwas then rgradually-raised to'.about? plus .tent'o' fifteen 'de'grec'scentigrade, whereupon seventmmil-liliters of glacial, acetic acid: was added: and ;themethylene: chloride removed under reduced; pressure.

Seven grams", of zinc} dust-was then= adde d-. to the cold; solution: at a; uniform ratefove irai; period-10f 1 ten. minut s, Wh le. k eping; the: reaction; t mp r:

. methylene chloride.

- er being stirred for fifteen minutes, the mixture was filtered and the filtrate poured into water. There was thus obtained 4.31 grams of maleic anhydride adduct of B-beta-acetoxybisnor- 5,7,9(11)-cholatrien-22-al, a fine white powder which melted at 187-197 degrees centigrade.

' To a solution of 0.30 gram of the maleic anhydride adduct of 3-beta-aceto'xybisnor-5,7,9(ll)- cholatrien-22-al, in thirty milliliters of ethanol, was added twenty milliliters of alcohol containing one percent 2,4-dinitrophenylhydrazine and three percent concentrated hydrochloric acid. The mixture was allowed to stand for one hour at room temperature and then placed in a refrigerator to complete precipitation of the yellow crystals. The precipitate was then collected and recrystallized from a mixture of chloroform and alcohol, to give the 2,4-dinitrophenylhydrazone of the maleic anhydride adduct of 3-beta-acetoxybisnor-5,7,9(11)-cholatrien-22-a1, melting at 269-271 degrees centigrade.

, Preparation 7.-Mal'ez'c anhydride adduct of 3- beta-acetoxybisnor-5,7,9 (11) -cholatrten-22-al A two-liter," round-bottom fiask was charged with fifty grams (0.93 mole) of dehydroergosteryl acetate maleic anhydride adduct and one liter of The solution was cooled to Dry-Ice temperature with a trichloroethylene "bath and ozonized oxygen passed through at a rate of 1200 milliliters of oxygen per minute (at this rate the ozonizer was producing about 36 "milligrams of ozone per minute). The flow of 'ozonized oxygen wasmaintained for 128 minutes, a total of 4608 milligrams (105 percent) of ozone being passed into the solution. The reaction mixture was transferred to a two-liter, round-bottom flask fitted with a capillary and a; condenser for downward distillation, 300 millilitersof acetic acid added, and the methylene chloride dis- 'tigrade. After additionQthe mixture was stirred for another twenty minutes and then. filtered. The precipitated zinc dust was washed by filtering 100 milliliters of acetic acid therethrough,

and the filtrategradually diluted with water (1100 to 1200 milliliters) until the product had been drowned out. The product was then cooled in the refrigerator overnight and filtered. The yield of crystalline product was 42 grams, assayin}; 89-95 percent of the desired aldehyde.

Preparation 8 In a manner essentially that described in Preparation 6, the following compounds were prepared.

(1) Maleic anhydride adduct of 3-beta-formoiwbisnor-5,7,9(11)-cholatrien-22-al, melting at 95-130 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 165-168 degrees centigrade.

(2) Maleic anhydride adduct of 3-beta-heptanoyloxybisnor-5,7,9 (ll) -cholatrien-2 2-al, melting at 197.5-199 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 253-257 degrees centigrade.

r (3) Dimethyl maleate adduct of 3-beta-ben- .10 zoyloxybisnor 5,7,9(11)- cholatrien-22al, melting at 183-187 degrees centigrade. 2,4-dinitrophenyl-hydrazone, melting at 224-249 degrees centigrade.

(4) Dimethyl maleate adduct of B-beta-acetoxybisnor-5,7,9 (11 -cholatrien-22-al, melting at 172-178 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 238 to 244 degrees centigrade.

(5) Dimethyl maleate adduct of 3-hydroxy- -bisnor-5,7,9(11)-cholatrien-22-al, melting at 163-170 degrees centigrade. 2,4-dinitrophenylhydrazone, melting at 250-254 degrees centigrade.

Preparation 9.--Dimethyl maleate adduct of 3- hydroxybisnor- 5,7,9 1 1 -oho-latrien'-22 -aZ V A solution of 2.69 grams (.005 mole) of the dimethyl ester of the maleic acid adduct of dehydroergosterol in eighty milliliters of; methylene chloride, cooled by a Dry-Ice and trichloroethylene bath, was treated with ozonized oxygen until 247.36 milligrams (.0051 mole) of ozone. was absorbed. The solution was then allowed to warm to room temperature, whereafter thirty milliliters of acetic acid was added and the methylene chloride removed in vacuo. While cooling ina waterbath at fifteen degrees centigrade, four grams of zinc dust was added in portions with stirring, the temperature being maintained between fifteen and twenty degrees centigrade. Stirring was continued for another fifteen minutes, whereafter the zinc was separated by filtration. The filtrate was diluted with water to cloudiness, extracted with ether, the ether extract washed with sodium bicarbonate and then with water to neutrality, the solution then dried over sodium sulfate and evaporated to dryness in vacuo. The residue was crystallized from aceticacid and water, giving 1.92 grams (81.5 percent of the theoretical), melting point 91-97 degrees centigrade, which yielded a dinitrophenylhydrazone .deriviative in 72.5 percent yield, melting p0int2l2-238 degrees centigrade. The aldehyde was recrystalized and found to. have a purified melting point of 163-170 degrees centigrade, while the dinitrophenylhydrazone derivative was recrystallized until a melting point of 250-254 degrees centigrade was attained v Preparation 10.- -MaZe'ic anhydrz'de adduct of 3 beta aceto-zry' 22 acetoacybz'snor 5,7,- 9(11) 20(22) -cholatetraene .11 at 186. to 193 degrees Centigrade. -Recry's.talliza tion of the'crude product fromv a mixture of acetone and pentane raised the melting point to 200 .5 to 202 degrees centigrade.

Preparation 11 r In ajmanneressentially that described in: Preparation 10, the following compounds were prepared:

(l) The dimethyl maleate adduct of 3-betabenzoyloxy 22 acetoxyblsnor 5,7','9(1l).,20- ('22) cholatetraene, which melted at 210 to 211 degrees Centigrade.

(2 'The dimethyl maleate adduct of 3-betaacetoxy 22 acetoxybisnor 5,7,9(11),20(22)- cholatetraene, which melted at 181 to 183 degrees centig'rade.=

In the same manner as'given above, 22acyloxy, e. g., formo'xy; acetoxy, propionoxy, butyroxy, valeroylo-xy, hexanolyloxy, heptanoyloxy, octanoyloxy, benzoyloxy, naphthoyloxy, and the like 3- acyloxyblsnor 5,7,9 ('11) ,20(22')- chol-atetraene adducts, are obtained from the compounds of Preparations 6, '7, and 8. Such representative compounds. include 3-formoxy-22-aoetoxybisno-r- 5;7,9(l1) ,20(22) cholatetraene, 3-propionoxy-22- acetoxybisnor 5,7,9(1l)-,20(22) cholatetraene, 3,22 dipropionoxybisnor 517,9(11) (22)- cholatetraene, 3,22 dibenzoyloxybisnor 5,7,9- (11) ,20-(22)-cholatetraene-, and 3-heptanoyloxy- 22 octanoyloxyblsnor 5, 7,9(11) ,20(22) cholatetraene adductswith maleicanhydride or maleic acid esters-such as the dimethyl maleate, diethyl maleate, dipropyl maieate, diisopropyl maleate, dibutyl maleate, dioctyl maleate, dibenzyl maleate, and the like.

Preparation 1 2.:.-Mal-eic anhyd ide adduct of 3'-beta.-aeetoxy-5:,7,9(11 -pregnatrien-20-one reduced pressure. v An additional thirty millilitersof glacial acetic acid was then. added and the ozonidedecomposed by adding seven grams or powdered zinc at a substantially uniform. rate while maintaining the reaction temperature between seventeen and twenty degrees centigrade.

The mixture was stirred for an additional twenty minut s, filtered, and the zinc washed with 140 milliliters of glacial acetic acid. The organic extracts were combined and diluted with seventy milliliters of water. When crystallization commenced, the rate of precipitation was increased by addition of two volumes of water. There was thus obtained 4.0 grams of the maleic anhydride adduct of 3-beta-acetoxy-5,7,9(1l) -pregnatrien- -20-one, which melted at 240 to 264.5 degrees centigrade- Several recrystallizations of the crude material from acetone raised the melting point to 263.5 to 264.5 degrees centigrade,

Preparation 13.-Dim.ethyl maleate. of 3-betaacet'ozcy-5,7,9 (11.) -pregnatrien-20-one A suspension of fifteen grams of 3-beta-acetairy-53,9611)-pregnatrien-20-one maleic anhychloride solution inlOO-milliliter portions over a period of three hours, all of the solid going into solution. At the end of this time the solution was reduced to one-half its original volume on thesteam bath to remove excess diazomethane, filtered, and concentrated to about 250 milliliters. Upon COOHIIg crystals of the dimethyl maleate of 3 -b.eta-acetoxy-5,7,9 l l) -pregnatrien-20-one. melting at 204-208 degrees centigrade, were deposited. The yield was 13.2 grams (87 percent of theory).

Preparation 14.--Dimethyl maleate of 3-beta- (rectory-5,7,9 (11) -pregnatrz'en-20-one Analysis:

Calculated for CzaHsaOr "2-, C, 69.86.; H. 1.68 Found 0,019.81; 1-1.7.86

By the same. manner of esterification, the following (3-3 esters were prepared: (1) dimethyl mal'eate adduct. of. 3-beta-formoxy-5,7,9(ll pre natrien-ZO-one. meltingv point. 223-230 degrees centigrade, and (2). the. dimethyl maleate adduct. of 3-betabenzoyloxy-5JZ,9(11)-pregnadri'de adduct in 320 milliliters of methanol was cooled in an ice-salt bath. A boiling chip was tl'ien-ZQ-one, melting point 250-254 degrees centigrade.

Prepamtion 1-5.Maleic anhydrz'de adduct of 3- bcta heptanoyloxy 5,7,9, (11) pregnatrien 20-one The maleic anhydride adduct of a-beta-heptanoyloxy-5.'l,9(ll) -pregnatrien-20-one. mettiu point 170-171 degrees centigrade, was prepared by refluxing the maleic acid adduotfi oi 3-betahydroxy-EJZBQJ) -pregnatrien20-one with heptylic anhydride and pyridine. for a period of twenty hours. and workin up. the reaction prod not in the usual manner.

Preparation. 16.- -Maieic acid adduct of .i-betahumour-51,901) -p1=egnatrien-20-one A solution of 4.52 grams (0.01.00 mole) of the maleic anhydride adduct of 3-beta-acetoxy- 5,7,9(1-1) -pregnatrien-z0-one, M. P. 263-2645 degrees eenti'grade, ina mixture of milliliters of 1,4-diox-ane and 400 milliliters of water containing four grams (0.10.. mole) of sodium hydroxide was allowed to stand at room temperature for two and one-half hours, whereupon a small quantity of plate-like crystals formed.

- These were dissolved by heating the mixture to seventy degrees centigrade for one-half hour. The reaction mixture was-then made acid with fifty milliliters of three normal hydrochloric acid and refrigerated to give a precipitate of 3.05 grams of needle-like crystals melting at 1'73- 177 degrees centigrade. On crystallization from a dioxane-water mixture, the compound melted at 211-215 degrees centigrade. The melting point was found to vary somewhat with the rate of heating.

' Analysis:

Calculated for C25H32O6 C, 70.07; H, 7.53 Found C, 69.80; H, 7.47

"Preparation 17.-Dimethyl maleate of 3-betahydrant/4,7,9 (11 pregnatrien-ZO-one in an ice-salt bath while a slight excess of di-.

azomethane in methylene chloride was added over a 25 minute period with stirring. Ten minutes after addition was complete, the solution was placed on a steam bath and concentia-ted rapidly to dryness. The residue was crystallized from an acetone-water mixture to give 0234' gram of the dimethyl maleate of Ii-betahydroxy 5,7,9(11) pregnatrien-20-one, melting at 193-195 degrees centigrade. After chroma- 'tog'r'aphy' and recrystallization, the compound melted at 192-197 degrees centigrade.

In thesame manner as given above, other dialkyl maleates, e. g., the diethyl, dipropyl, diisopropyl, dibutyl, dioctyl, dicyclopentyl, dicyclohexyl, dibenzyl, and the like maleates of 3-hydroxy-5,7,9(11) -pregnatrien-20-one are prepared from 3 hydroxy. 5,7,9(11) pregnatrien-ZO-one maleic acid adduct and the appropriate diazoalkane, or by other equivalent esterification procedure.

Preparation 18.-Maleic anhydride adduct of 3- beta-hydromy-5,7,9 (11) -pe'gnatrien-20-one Similarly the maleic anhydride adduct of 3- beta' hydroxy 5,7,9(11) pregnatrien-20-one,

melting point about 195 degrees centigrade, was

prepared by refluxing the maleic acid adduct of 3 {beta-hydroxy 5,7,9(11) pregnatrien-20-one with Dowtherm for eight hours. The 3-hydroxy-maleic anhydride adduct is also obtained,

by 1 heating the 3-hydroxy maleic acid adduct to'just above its melting point, which procedure causes water to be evolved, with the closing of the anhydride ring.

In the same. manner as given above, still other acid, maleic acid anhydride, and maleic acid diester adducts. Such compounds include the 3- formoxyor 3-hydroxy-5,7,9(11) -pregnatrien-20- onefmaleic acid, maleic acid anhydride, dimethyl maleate, diethyl maleate, dibutyl maleate, dioctyl maleate, diisopropyl maleate, dibenzyl maleate,

and like adducts; the corresponding 3-propionoxy,= butyroxy, valeroxy, hexanoyloxy, heptanoyloxy; octanoyloxy, naphthoyloxy, benzoyloxy, and similari20-ketone adducts, including, for example, 3- pr'opionoxy-5,7,9 1 1) -pregnatrien-20-one dipro- Dyl maleate, 3-benzoy1oxy-5,7,9(11)-pregnatrien;

maleate, 3 heptano1oxy'-" 20- one dibenzoyl 5,7,9(11)-pregnatrien-20-one dimethyl maleate, 3,-va1eroy1oxy-5,7,9 1 1) -pregnatrien-20-one maleicacid anhydride adducts, and the like. The 3- acyloxy compounds are converted to the corresponding 3-hydroxy compounds as indicated in the foregoing preparations.

.EEanampZe 1.Maleic anhydride adduct of 5,7,9 (11) -pregnattrien-3,20-dione 3 beta hydroxy 5,7,9(11) -pregnatrien-20-one suspended in 21.4 milliliters of acetic acid. The temperature was held at 20-22 degrees centigrade during addition, whereafter the solution was allowed to stand for two hours at room temperature. The reaction mixture was concentrated in vacuo to a heavy syrup, which gave 1.67 grams of a gray-purple solid on stirring with fifty milliliters of Water. This was suspended in fifteen milliliters of acetic anhydride, the mixture heated for three hours on the steam bath, and then poured over ice, giving 0.92 gram of the maleic anhydride adduct of 5,7,9(11),-pregnatrien-3,20-dione, melting at 182-193 degrees centigrade.

Example 2.-Maleic acid adduct of 5,7,9 11

pregnatriLen-SJO-dione A suspension of: 3.93 grams of the maleic acid adduct of 3-beta-hydroxy-5,7,9(1l) -pregnatrien- 20-one in seventy milliliters of-acetic acid was cooled in a water bath at eighteen degrees centigrade and a solution of 0.58 gram of chromium trioxide in a mixture of 0.4 milliliter of water, forty milliliters of acetic acid, and 0.2 milliliter of sulfuric acid added dropwise with stirring over a period oi an hour. The reaction mixture. was allowed to stand for one hour, then concentrated in vacuo at a temperature below forty degrees centigrade until very little liquid-remained. A small amount of Water was then added and the residue dissolved. The solution was diluted to a volume of 100 milliliters with aqueous sodium chloride, and 3.14 grams of precipitate obtained. The precipitate was dissolved in 100 milliliters of one per cent aqueous sodium hydroxide solution and precipitated by addition of hydrochloric acid. The yield of the maleic acid 'adduct of 5,7,9(11)- pregnatrien-3,20-dione was 1.27 grams, melting at 153-158 degrees centigrade.

Example 3.-Dimethyl maleate adduct of 5,7,9 (11) -pregnatrien-3,20-dione An excess of diazomethane in methylene chloride solution was added to 0.40 gram of the maleic anhydride adduct of 5,7,9(11)-pregnatrien-3,20- dione in five milliliters of methanol. The reaction mixture was allowed to stand for three hours at room temperature, and was then evaporated to dryness on the steam bath. The residue was chromatographed over twenty grams of Fishers alumina, giving a main fraction weighing 375 milligrams. This fraction was crystallized from aqueous acetone, to give crystals of the dimethyl maleate of 5,7,9(11) pregnatrien 3,20 dione which melted at 138-143 degrees centigrade. The same product is produced by oxidation of the dimethyl maleate adduct of 3-hydroxy- 5,7,9(11) -pregnatrien-20-one according to the manner of the preceding examples.

In the same manner, other dialkyl maleate adducts of 5,7,9(11) -pregnatrien-3,20-dione are prepared from the corresponding dialkyl maleate of the 3-hydroxy compound. Such compounds include, for example, the 5,7,9(11)pregnatrien- 3,20-dione diethyl, dipropyl, diisopropyl, dibutyl, diamyl, dihexyl, diheptyl, dioctyl maleate adducts, and the like.

It is to be understood that the invention is not to be limited to the exact details of operation or exact compounds shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

ecuees 15 Weclaim: I. A v,,' ,9=(;l-L)/-pregnatrienr3,zfl-dione adduc of th formula:

'- GHs wherein A is an adduct radical of a dienoph-ile oi the group consisting, of maleic acid, maleic anhydride, and maleic acid lower-alkyl diesters, wherein the esterifying lower-alkyl groups contain from one to eight carbon atoms, inclusive. 2; Maleic anhydri'de, adductof 55,9611)- pregnatrien-azo-dione.

3. Maleic acid adduct of 5,7,9(11 )-pregnatrien-3,20-dione.

4. Dimethyl maleate adduct of 5,7;9("1l)-pregnatrien-3,20-dione-. -5'.-Process for the production of 5,7;9(11) pregnadien-fiiJO-di'one adducts which includes the. step of oxidizing the 3-hydroxy group of a 3 -hydrexy-5,7,9(1l)-pregnatrien-20one adduct 01 the formula:

r-rO wherein A is an addict radical of a dienophile selected from the group consisting of; maleic acid, maleic acid anhydride, and maleic acid diesters wherein the esterifying groups contain up to and including eight carbon atoms, to convert the 3-hydroxy group to a 3-keto group, said oxida-- tion being. conducted by mixing the starting adduct with from. one to four molar equivalents of chromic acid in an acetic acid, medium, in the presence of. a catalytic quantity of. sulfuric acid, at a temperature ofv about sixteen. to. twenty-six degrees, centigrade; and. recovering the 3-keto ad'duct from the reaction product.

6,. Process of claim 5, wherein the starting adduct is 3-hydroxy-5,7,9(ll) -pregnatri en-20-one maleic. anhydride. adduct.

7., Process of, claim 5, wherein the starting ad.- duct. is 3-hydroxy-5 ,7, 9(11.) -pregnatrien-20-one maleio acid adduc 8. Process, of claim 5,, wherein the; starting adduct is a 3hydroxy-5., 7,9(11)-pregnatrien-2Q- one dialkyl, maleate adduct.

9. Process of. claim 5,, wherein the starting adrduct. is 3-hydroxy-5,7,9(1l)-pregnatrien20-one dimethyl maleate adduct.

ROBERT H. LEVIN. A VERN' MQINTOSHi JR GEORGE B. SPERO.

REFERENCES CITED 

1. A 5,7,9(11)-PREGNATRIEN-3,20-DIONE ADDUCT OF THE FORMULA: 